SIMPLICIAL GALOIS DEFORMATION FUNCTORS

Y Cai (1) , J Tilouine (1)

1 LAGA - Laboratoire Analyse, Géométrie et Applications

In [GV18], the authors showed the importance of studying simplicial generalizations of Galois deformation functors. They established a precise link between the simplicial universal deformation ring R prorepresenting such a deformation problem (with local conditions) and a derived Hecke algebra. Here we focus on the algebraic part of their study which we complete in two directions. First, we introduce the notion of simplicial pseudo-characters and prove relations between the (derived) deformation functors of simplicial pseudo-characters and that of simplicial Galois representations. Secondly, we dene the relative cotangent complex of a simplicial deformation functor and, in the ordinary case, we relate it to the relative complex of ordinary Galois cochains. Finally, we recall how the latter can be used to relate the fundamental group of R to the ordinary dual adjoint Selmer group, by a homomorphism already introduced in [GV18] and studied in greater generality in [TU20].

Domaines: Mathématiques [math]; Théorie des nombres [math.NT]

Y Cai, J Tilouine. SIMPLICIAL GALOIS DEFORMATION FUNCTORS. 2020. ⟨hal-02892144⟩